docs: def create_char(self, location, pattern):
          """Fill one of the first 8 CGRAM locations with custom characters.
          The location parameter should be between 0 and 7 and pattern should
          provide an array of 8 bytes containing the pattern. E.g. you can easyly
          design your custom character at http://www.quinapalus.com/hd44780udg.html
          To show your custom character use eg. lcd.message('\x01')
          """
          # only position 0..7 are allowed
          location &= 0x7
          self.write8(LCD_SETCGRAMADDR | (location << 3))
          for i in range(8):
              self.write8(pattern[i], char_mode=True)